ML20082T137

Interim Deficiency Rept,Item 105 Re Thermal Separation Criteria Violations in Drywell.Initially Reported on 831104. Design Change Issued,Revising Electrical Specs for Insp Purposes in Drywell.Mods Will Be Made as Necessary

ML20082T137
Person / Time
Site:	Fermi
Issue date:	12/05/1983
From:	Wells D DETROIT EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
105, 10CFR-050.55E, 10CFR-50.55E, DER-831205-01, DER-831205-1, EF2-66482, NUDOCS 8312150173
Download: ML20082T137 (2)

Text

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. c> - .7 Donald A. Wells s Manager.ouahty Ascurance -

f 4313) 237-9657

2000 Secor.d Avenue 31 3 December 5, 1983 EF2-66482 Mr. James'G. Keppler, Regional Administrator Region.III U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen-Ellyn, Illinois 60137

Subject:

Report ' of 10CFR50.55(e) Item on Thermal Separation Criteria Violations (#105)

Dear Mr. Keppler:

- On November:4, 1983, Detroit Edison's Mr. J.E. Durkin, Quality

. Engineer - Construction Quality Ascurance, telephoned Mr. P. Pelke of

- NRC Region III to report on Thermal Separation Criteria violations in

. the drywell at the Fermi' 2 site.

A number of instances exist where thermal separation between electrical cables and hot pipes or equipment is.less than specified. This could

~ cause'a premature. failure of' electrical cables.-

The Engineering Research Department did studies on heat transfer from steam pipes'to electrical conduits and trays. Various curves were developed between pipe distance / diameter ratios vs pipe skin tempera-

- ture and temperature rise.- Tables were developed from these curves.

Design Calculation 2119 " Calculation of Separation Distance to be Maintained Between Electrical Conduits, Trays and Steam Lines (Mechanical Hot Pipes)" was issued listing the ' curves and the tables.

Separation distance between electrical conduits or trays and steam pipes can.be calculated from the tables in DC 2119.

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Edison Field Endineering has issued a design change revising the

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electrical specification for inspection purposes in the drywell. This design change is based on DC 2119. Currently, a walkdown is being performed in the drywell per the design change. Any violations will be evaluated by 'the Engineering Research Department and the Generation Engineering Department on 'a case-by-case basis and disposed accordingly.

l If any distance between steam pipes and electrical conduits or trays is found to be unacceptable, modifications will be made to correct any problems.

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Mr. James'G. Keppler,' Regional Administrator

'- December 5, 1983 _ ,. .~

EF2-66482 Page'2 Another report ion'this item,.either. interim or final, will be sent when'further'information is available. If you have questions concern-

- ing this matter, please contact'Mr. G.M..Trahey,: Assistant Director -

Project.; Quality Assurance.

.Very..truly-yours, r i.

Y)]

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DAW /EHN/cp ,

cc: Mr. Richard DeYoung, Director-Office of Inspection and Enforcement

. f. LU;S. Nuclear-Regulatory Commission Washington,LD.C.= 20555

Mr. Paul Byron, Senior Resident Inspector U.S. Nuclear Regulatory Commission

.6450 North Dixie Highway-Newport,' Michigan 48166 V

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